CN116602705A - An ultrasonic pulse Doppler blood flow measurement method and device - Google Patents

Abstract

The invention discloses an ultrasonic pulse Doppler blood flow measurement method and device, wherein the blood flow measurement method includes: determining the physical position of the pulse Doppler probe; based on the current physical position of the probe, determining the position of several array elements in the probe Arranging the formed array, and determining the edge position of the array; based on the blood flow direction of the position to be detected, adjusting the position of the sub-array for transmitting and receiving ultrasound to the edge position, and determining the position of the sub-array; based on the sub-array Quantitative measurement of blood flow by pulsed ultrasound Doppler. By only modifying the physical position of the array elements participating in the current electronic beamforming, the steering angle is automatically expanded, and even the steering angle that may have reached the user-configurable limit (plus or minus 20 degrees) can be further expanded to maximize Automatically meet the measurement angle requirements of Doppler.

Description

An ultrasonic pulse Doppler blood flow measurement method and device

technical field

The invention relates to the technical field of Doppler measurement, in particular to an ultrasonic pulse Doppler blood flow measurement method and device.

Background technique

The blood flow velocity of the human body is a very important indicator in clinical diagnosis, which can be measured by using ultrasonic pulsed Doppler technology, but the ultrasound equipment relies on the Doppler angle being less than 60 degrees when quantitatively measuring the blood flow velocity. Otherwise, the measurement error will be too large to affect the clinical judgment.

In the past, the problem can be partially solved by the doctor pressing the probe on the patient's body surface and adjusting the steering angle of the beam. With the development of computing technology, the device can use image algorithms to automatically calculate the direction of blood flow, and then the device automatically adjusts the steering angle based on the calculated direction of blood flow. However, the above two methods have limitations. The former requires manual operation by the physician. This operation process is time-consuming and will also affect the position of the probe, resulting in repeated operations; the latter requires the current vascular anatomical information to be available in the image. To meet the requirements of the preset algorithm, the execution of the algorithm has calculation requirements for software and hardware, which will lead to limitations in application; moreover, if the actual blood flow direction is not satisfied after applying the maximum steering angle, inaccurate results will still be obtained , need to adjust the position of the probe.

Contents of the invention

The present invention provides an ultrasonic pulse Doppler blood flow measurement method and device to solve the above-mentioned problems in the prior art.

The invention provides a method for measuring ultrasonic pulsed Doppler blood flow, the method comprising:

S100, determining the physical position of the pulse Doppler probe;

S200, based on the current physical position of the probe, determine the array formed by the arrangement of several array elements in the probe, and determine the edge position of the array;

S300. Based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasonic waves to shift to the edge position, and determine the position of the sub-array;

S400, performing quantitative measurement of ultrasonic pulse Doppler blood flow based on the position of the subarray.

preferred,

Preferably, the S200 includes: when the array formed by arranging several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array;

Correspondingly, the S300 includes: the first edge position is connected with the position to be detected to form a first straight line; the first straight line and the direction of the blood vessel are set at a first acute angle, and the second edge position and the position to be detected are set at a first acute angle. The positions are connected to form a second straight line; the second straight line and the direction of the blood vessel are set as a second acute angle, and it is judged whether the first acute angle is smaller than the second acute angle, and if so, adjust the sub-arrays for transmitting and receiving ultrasonic waves to the first of the array An edge position offset; if the first acute angle is greater than the second acute angle, adjust the sub-array for transmitting and receiving ultrasonic waves to the second edge position of the array;

The direction of the blood vessel is a scalar quantity, and the relationship between the direction of the blood vessel and the direction of blood flow is as follows: when the direction of blood vessels is the same, the direction of blood flow includes: from left to right of the blood vessel, or from right to left of the blood vessel.

Preferably, the S200 includes: when the array formed by arranging several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array;

Correspondingly, the S300 includes:

S301, based on the current physical position of the probe, adjust the offset of the sub-array to the first edge position, and monitor whether the Doppler included angle is less than or equal to the standard Doppler included angle, if yes, execute step S302; if not, execute step S303;

S302, adjusting the offset of the sub-array for transmitting and receiving ultrasonic waves to the first edge position of the array, and determining the first edge position as the position of the sub-array;

S303, adjusting the offset of the sub-array for transmitting and receiving ultrasonic waves to the second edge position of the array, and determining the second edge position as the position of the sub-array.

Preferably, the S200 includes: when the array formed by arranging several array elements is a two-dimensional array, the edge positions include several edge positions;

Correspondingly, the S300 includes: each edge position is connected with the position to be detected to form several straight lines, and each straight line forms an acute angle with the direction of the blood vessel, and the position of the array element corresponding to the straight line with the smallest acute angle is judged, and the array element is determined. The edge position corresponding to the element is set as the position of the sub-array.

Preferably, said S300 also includes:

S304, determining that the number of continuous sub-arrays transmitting and receiving ultrasonic waves in the probe is a selected number;

S305, taking the outermost array element in the edge position of the array as a reference, continuously select array elements of the same number as the selected number inward as sub-arrays for transmitting and receiving ultrasonic waves, and determine the positions of the sub-arrays.

Preferably, before said S100 includes:

S500, start the ultrasonic pulse Doppler measurement mode;

S600, judging whether the offset policy condition is met, if yes, execute step S100, if not, execute step S700;

S700, using the current configuration parameters of ultrasonic pulse Doppler to perform quantitative measurement of ultrasonic pulse Doppler blood flow.

Preferably, said S300 also includes:

S306. When the position of the sub-array is shifted toward the edge position, a plurality of shift positions are formed, and according to the plurality of shift positions, the positions of the sub-array include multiple;

S307, the positions of multiple sub-arrays are selected by the user through the interactive device, and the ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the current configuration parameters of the ultrasonic pulse Doppler according to the positions of the sub-arrays selected by the user.

Preferably, said S400 includes:

S401, based on the pulse Doppler spectrum received by the sub-array, use a spectrum analysis algorithm to input fixed-length data on the pulse Doppler spectrum, multiply the fixed-length data by the Hamming window each time, and use FFT processing to obtain Doppler power spectrum of Le data;

S402, after the first spectrum analysis algorithm processing is completed, move the input Doppler data backward by the data of the step length, take the fixed-length Doppler data for the next spectrum analysis algorithm processing, and continuously sample This operation is looped over the Doppler data to obtain a time-varying power spectrum. The step length is determined by the current scanning speed;

S403, after the spectrum analysis algorithm processes the current Doppler data, the power spectrum of the data will be obtained, the power spectrum corresponds to a spectral line in the dynamic power spectrum diagram, and the amplitude of the spectral line is mapped to an index table of gray values, Display coded according to the color indicated by the index table of grayscale values. The larger the amplitude, the larger the gray value, indicating that the power at this frequency is high;

S404, transfer to process the next set of data after processing the current data, and draw the dynamic power spectrum diagram of the Doppler signal after obtaining the continuous power spectrum;

S405. Perform noise reduction processing on the dynamic power spectrum, and use the noise-reduced dynamic power spectrum as a basis for quantitative ultrasound pulse Doppler blood flow.

Preferably, performing noise reduction processing on the dynamic power spectrum in said S405 includes:

S4051, extracting all characteristic components of the signal in the dynamic power spectrum;

S4052, analyzing the correlation relationship between two feature components; the correlation between different feature components is represented by an inner product;

S4053, if the main feature component is determined to be a clutter component according to the frequency threshold, calculate the correlation between the remaining feature components and the main feature component, and if the correlation is greater than a certain set correlation threshold, then judge that the feature component belongs to clutter Feature space, remove high feature components from the signal;

S4054. Form a set of clutter feature spaces according to step S4053, and reconstruct the filtered signal based on the set of clutter feature spaces.

The present invention also provides an ultrasonic pulse Doppler blood flow measurement device, which includes: an ultrasonic pulse Doppler probe, an interactive device, and a measurement control module;

The measurement control module is respectively connected to the ultrasonic pulse Doppler probe and the interactive device;

The ultrasonic pulsed Doppler probe includes several array elements arranged in an array, and the continuous several array elements are controlled by the measurement control module to transmit and receive ultrasonic waves to form sub-arrays;

The interaction device is used for the control operation interaction between the user and the measurement control module;

After the ultrasonic pulse Doppler blood flow measurement device is started, the interactive device displays whether the offset strategy condition is met, and if the offset strategy condition is met, after the ultrasonic pulse Doppler probe determines the physical position, based on the current physical position of the probe, determine The edge position of the array, and based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasound to offset the edge position, determine the position of the sub-array, and provide the user with sub-array position options, After the user selects the position of the corresponding sub-array through the interactive device, the ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the position of the sub-array; Quantitative measurement of Puller blood flow.

Compared with the prior art, the present invention has the following advantages:

The present invention provides an ultrasonic pulse Doppler blood flow measurement method and device, wherein the blood flow measurement method includes: determining the physical position of the pulse Doppler probe; and determining the arrangement of several array elements in the probe based on the current physical position of the probe Form the array, and determine the edge position of the array; based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasound to the edge position, and determine the position of the sub-array; based on the sub-array position for quantitative measurement of ultrasound pulsed Doppler blood flow. By only modifying the physical position of the array elements participating in the current electronic beamforming, the steering angle is automatically expanded, and even the steering angle that may have reached the user-configurable limit (plus or minus 20 degrees) can be further expanded to maximize Automatically meet the measurement angle requirements of Doppler.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention. In the attached picture:

Fig. 1 is a flow chart of an ultrasonic pulse Doppler blood flow measurement method in an embodiment of the present invention;

Fig. 2 is the structure schematic diagram of the linear array in the probe in the embodiment of the present invention;

Fig. 3 is a schematic diagram of the principle of subarray position offset increasing steering angle in an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of an ultrasonic pulse Doppler blood flow measurement device in an embodiment of the present invention.

Detailed ways

The preferred embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention.

An embodiment of the present invention provides an ultrasonic pulse Doppler blood flow measurement method, please refer to Figure 1, the method includes:

S100, determining the physical position of the pulse Doppler probe;

S200, based on the current physical position of the probe, determine the array formed by the arrangement of several array elements in the probe, and determine the edge position of the array;

S300. Based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasonic waves to shift to the edge position, and determine the position of the sub-array;

S400, performing quantitative measurement of ultrasonic pulse Doppler blood flow based on the position of the subarray.

The working principle of the above technical solution is: the solution adopted in this embodiment is to determine the physical position of the pulse Doppler probe; based on the current physical position of the probe, determine the array formed by the arrangement of several array elements in the probe, and determine the array edge position; based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasonic waves to offset to the edge position, and determine the position of the sub-array; perform ultrasonic pulse Doppler blood flow based on the position of the sub-array Quantitative measurement.

It should be noted that the traditional operation mode A: after finding the blood vessel, the operator activates the ROI display, moves the ROI to the center of the blood vessel, and then adjusts the steering angle of the beam and the position of the probe respectively, and the doctor judges that the Doppler included angle reaches the standard Once in range, start quantitative pulse Doppler detection.

In addition, image-based blood vessel recognition method B: after the operator finds the blood vessel, he activates the ROI display, and then the algorithm that can analyze the image content will be executed. Adjust the steering angle of the beam, and start the pulse Doppler quantitative detection after judging that the Doppler angle reaches the standard range.

However, the existing above two methods have the following disadvantages:

Method A: requires high operator skills and takes a long time; if the operator cannot understand the Doppler angle limit, it will lead to errors in actual measurement results and affect clinical diagnosis.

Mode B: The algorithm for image recognition is highly demanding, and it is easy to fail to work due to the complexity of the ultrasound image, and the stability is insufficient; the computing power of image recognition requires hardware to meet, otherwise the function will not be available because the calculation takes too long; if the obtained Ultrasound images that cannot be effectively recognized by the algorithm will lead to more serious time consumption and even wrong measurement results.

The present invention utilizes the position of the array element of the currently activated ultrasonic probe to perform physical position offset at the timing of starting the pulse Doppler measurement quantitative detection, while keeping the physical position of the probe unchanged, the array elements participating in the emission Move to the position at the edge of the probe to minimize the angle between the ultrasonic pulse and the blood flow direction (Doppler angle), thereby minimizing the error of Doppler measurement results and providing accurate measurement results for clinical diagnosis.

The beneficial effect of the above technical solution is: the solution provided by this embodiment can automatically expand the steering angle by only modifying the physical position of the array elements participating in the current electronic beamforming, and even the limit that may have reached the user-configurable limit can be increased. The steering angle (plus or minus 20 degrees) is further expanded to automatically meet the Doppler measurement angle requirements to the greatest extent.

In another embodiment, the S200 includes: when the array formed by arranging several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array ;

Correspondingly, the S300 includes:

The first edge position is connected to the position to be detected to form a first straight line; the first straight line is set to form a first acute angle with the direction of the blood vessel, and the second edge position is connected to the position to be detected to form a second straight line; The second straight line and the direction of the blood vessel are set as a second acute angle, and it is judged whether the first acute angle is smaller than the second acute angle, and if so, the sub-array for transmitting and receiving ultrasonic waves is adjusted to shift toward the first edge position of the array; if the second An acute angle is greater than the second acute angle, and the sub-array for transmitting and receiving ultrasonic waves is adjusted to shift toward the second edge position of the array;

The direction of the blood vessel is a scalar quantity, and the relationship between the direction of the blood vessel and the direction of blood flow is as follows: when the direction of blood vessels is the same, the direction of blood flow includes: from left to right of the blood vessel, or from right to left of the blood vessel.

In a two-dimensional plane, if blood vessels are in a horizontal position, blood flow can be from left to right or right to left. The direction of blood flow can be directional, and this embodiment does not specify the direction of the direction of the blood vessels. Therefore, the direction of the blood vessels and the first straight line or the second straight line must present an acute angle or an obtuse angle (a 90° right angle between the two is not considered here. Case).

The working principle of the above technical solution is: the solution adopted in this embodiment is that the S200 includes: when the array formed by arranging several array elements is a one-dimensional array, the edge position includes the first edge position at the head of the array and The second edge position located at the tail of the array; correspondingly, the S300 includes: the first edge position is connected with the position to be detected to form a first straight line; the first straight line and the direction of the blood vessel are set at a first acute angle, The second edge position is connected with the position to be detected to form a second straight line; the second straight line and the direction of the blood vessel are set as a second acute angle, and it is judged whether the first acute angle is smaller than the second acute angle, and if so, adjust the emission and The sub-array receiving ultrasonic waves is offset to the first edge position of the array; if the first acute angle is greater than the second acute angle, the sub-array for transmitting and receiving ultrasonic waves is adjusted to offset to the second edge position of the array; the direction of the blood vessel is a scalar , the relationship between the blood vessel direction and the blood flow direction is as follows: when the blood vessel direction is the same, the blood flow direction includes: from left to right of the blood vessel, or from right to left of the blood vessel.

The solution provided in this embodiment is to find out how to find the position of the sub-array that conforms to the Doppler angle by adjusting the position of the sub-array that emits ultrasound. Measurement.

In another embodiment, the S200 includes: when the array formed by arranging several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array ;

Correspondingly, the S300 includes:

S301, based on the current physical position of the probe, adjust the offset of the sub-array to the first edge position, and monitor whether the Doppler included angle is less than or equal to the standard Doppler included angle, if yes, execute step S302; if not, execute step S303;

S302, adjusting the offset of the sub-array for transmitting and receiving ultrasonic waves to the first edge position of the array, and determining the first edge position as the position of the sub-array;

S303, adjusting the offset of the sub-array for transmitting and receiving ultrasonic waves to the second edge position of the array, and determining the second edge position as the position of the sub-array.

The technical principle of the above technical solution is: based on the current physical position of the probe, adjust the offset of the sub-array to the first edge position, monitor whether the Doppler included angle is less than or equal to the standard Doppler included angle, and if so, adjust the distance between transmitting and receiving ultrasonic waves. The sub-array is offset to the first edge position of the array, and the first edge position is determined to be the position of the sub-array; if not, the sub-array that adjusts the emission and reception of ultrasonic waves is offset to the second edge position of the array, and the second edge position is determined to be The location of the subarray.

This embodiment provides a maximum of two subarray position adjustments to accurately obtain Doppler blood flow measurement results. If the first edge position meets the measurement requirements, the measurement can be performed directly. If not, it can be directly adjusted to the second edge position. If the position of the two edges is shifted, the measurement can be carried out directly without the need for multiple measurements.

Specifically, the Doppler blood flow measurement instrument is introduced as follows: the probe is composed of multiple physical array elements, which are generally arranged in a one-dimensional manner in a straight line/curve manner (there are also entities arranged in two dimensions).

The sub-array is composed of a part of continuous array elements in the probe, which participates in the transmission and reception of an actual ultrasonic wave. The beam synthesis can be performed by controlling the actual transmission time of each array element, including the adjustment of the steering angle.

Synthetic beams can be formed by determining the focus position and participating sub-arrays.

When pulse Doppler detects the blood flow of blood vessels on the surface of the body, the array element position offset is used to increase the steering angle to minimize the Doppler angle.

For example, Fig. 2 is a schematic diagram of the structure of the linear array in the probe. As shown in Fig. 2, 1-14 are array elements arranged in an array to form an array, and the overall linear array is combined into a probe. Among them, the sub-array is composed of 1-4, and the focal point of the synthesized beam is point P.

As another example, Fig. 3 is a schematic diagram of the principle of increasing the steering angle by subarray position offset. When 5-9 array elements are used as subarrays to transmit ultrasonic waves, the direction of the synthesized beam is ₀ , L represents the direction of blood flow, and the direction of the synthesized beam is B ₀ The angle between B 1 and the direction of blood flow is α, and the direction of the combined beam is shifted from B ₀ to B ₁ by shifting the position of the subarray in this embodiment, so the angle between B ₁ and the direction of blood flow L is β, the ratio of β to The smaller α, in the Doppler effect, the smaller the included angle, the more accurate the detection result.

Combined with this embodiment, when using 5-9 array elements as sub-arrays to emit ultrasound, it may not meet the Doppler angle, set the position corresponding to 1-4 array elements as the first edge position, and the corresponding 10 The position corresponding to the -14 array element is used as the second edge position. Through the example of this embodiment, it can be illustrated that the angle between the second straight line formed by the connection line between the second edge position and the position to be detected and the blood flow direction is smaller. Therefore, it can be The sub-array for transmitting and receiving ultrasonic waves is adjusted to offset to the second edge position of the array, and the second edge position is determined as the position of the sub-array.

Doppler blood flow measurement can be accurately performed by adjusting the offset direction of the sub-array that transmits and receives ultrasound twice at most, without multiple experimental adjustments to find the position that meets the Doppler angle and improve Doppler Accuracy of blood flow measurement and improvement of measurement efficiency.

It should be noted that the steering angle in English refers to the angle between the direction of the beam and the axial direction of the probe in ultrasound. The normal situation is as shown in the B ₀ direction in Figure 2. At this time, the steering angle is 0. If the actual beam direction changes from ₀ to B ₁ , then the steering angle increases from 0 to non-zero. At this time, the steering angle is equal to Angle between B ₀ and B ₁ .

In another embodiment,

The S200 includes: when the array formed by arranging several array elements is a two-dimensional array, the edge position includes several edge positions;

Correspondingly, the S300 includes: each edge position is connected with the position to be detected to form several straight lines, and each straight line forms an acute angle with the direction of the blood vessel, and the position of the array element corresponding to the straight line with the smallest acute angle is judged, and the array element is determined. The edge position corresponding to the element is set as the position of the sub-array.

The working principle of the above technical solution is: the solution adopted in this embodiment is that the S200 includes: when the array formed by arranging several array elements is a two-dimensional array, the edge position includes several edge positions; correspondingly, the S300 includes: each edge position is connected with the position to be detected to form a number of straight lines, each line forms an acute angle with the direction of the blood vessel, and the position of the array element corresponding to the straight line with the smallest acute angle is judged, and the edge position corresponding to the array element is determined. Set to the position of the subarray.

When the array is a two-dimensional array, based on the same principle, the acute angle between the straight line and the direction of the blood vessel is determined, and the smallest acute angle is determined from the multiple acute angles formed. The acute angle is formed by a certain straight line and the direction of the blood vessel, so , the straight line can be determined. After the straight line is determined, it can be determined which edge position and the position to be detected form the straight line. Therefore, the corresponding edge position can be found out, and the sub-arrays for transmitting and receiving ultrasonic waves can be adjusted to find out the direction of the array. The Doppler blood flow measurement scheme can be accurately realized with the edge position offset.

In another embodiment, the S300 also includes:

S304, determining that the number of continuous sub-arrays transmitting and receiving ultrasonic waves in the probe is a selected number;

S305, taking the outermost array element in the edge position of the array as a reference, continuously select array elements of the same number as the selected number inward as sub-arrays for transmitting and receiving ultrasonic waves, and determine the positions of the sub-arrays.

The working principle of the above-mentioned technical solution is: the solution adopted in this embodiment is to determine the number of continuous sub-arrays transmitting and receiving ultrasonic waves in the probe as the selected number; Continuously select the same number of array elements as the selected number as the sub-arrays for transmitting and receiving ultrasonic waves, and determine the positions of the sub-arrays.

Shifting the subarray to other positions of the probe can reduce the Doppler angle, thereby increasing the measurement accuracy.

In another embodiment, before S100 includes:

S500, start the ultrasonic pulse Doppler measurement mode;

S600, judging whether the offset policy condition is met, if yes, execute step S100, if not, execute step S700;

S700, using the current configuration parameters of ultrasonic pulse Doppler to perform quantitative measurement of ultrasonic pulse Doppler blood flow.

The working principle of the above technical solution is: the solution adopted in this embodiment is to start the ultrasonic pulse Doppler measurement mode; judge whether the migration strategy condition is satisfied, if it is satisfied, perform step S100, if not satisfied, the execution step adopts ultrasonic pulse Doppler Doppler current configuration parameters for quantitative ultrasound pulse Doppler blood flow measurement.

Determine whether the offset strategy is applicable, and if applicable, perform an offset to the edge of the sound head (the actual implementation can independently set the offset to the near end/far end), if it is not applicable, directly use the default parameters; if an offset operation occurs , then identify the original user ROI position on the UI and the ROI position after the strategy is applied; activate the strategy selection button; the user judges whether the current strategy is satisfactory, if satisfied, operate according to the original strategy, and if not satisfied, use the activated button Adjust the strategy to support the cycle of this step; after the isopulse Doppler has completed multiple measurement cycles for the blood flow velocity of the patient's vessels, the user can adopt a freezing strategy and then measure the actual blood flow velocity. Applying subarray offset will reduce the Doppler angle, reduce measurement error and improve accuracy.

In another embodiment, the S300 also includes:

S306. When the position of the sub-array is shifted toward the edge position, a plurality of shift positions are formed, and according to the plurality of shift positions, the positions of the sub-array include multiple;

S307, the positions of multiple sub-arrays are selected by the user through the interactive device, and the ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the current configuration parameters of the ultrasonic pulse Doppler according to the positions of the sub-arrays selected by the user.

For example, the image of the protection device UI will display the actual PW sampling line position after the policy is applied, as well as the old position before the application. The control panel of the UI will display option buttons [Edge 1/Edge 2/Center/Original Position] that support adjustments; users can use this button to quickly apply new strategies for situations that they are not satisfied with.

In another embodiment, the S400 includes:

S401, based on the pulse Doppler spectrum received by the sub-array, use a spectrum analysis algorithm to input fixed-length data on the pulse Doppler spectrum, multiply the fixed-length data by the Hamming window each time, and use FFT processing to obtain Doppler power spectrum of Le data;

S402, after the first spectrum analysis algorithm processing is completed, move the input Doppler data backward by the data of the step length, take the fixed-length Doppler data for the next spectrum analysis algorithm processing, and continuously sample This operation is looped over the Doppler data to obtain a time-varying power spectrum. The step length is determined by the current scanning speed;

S403, after the spectrum analysis algorithm processes the current Doppler data, the power spectrum of the data will be obtained, the power spectrum corresponds to a spectral line in the dynamic power spectrum diagram, and the amplitude of the spectral line is mapped to an index table of gray values, Display coded according to the color indicated by the index table of grayscale values. The larger the amplitude, the larger the gray value, indicating that the power at this frequency is high;

S404, transfer to process the next set of data after processing the current data, and draw the dynamic power spectrum diagram of the Doppler signal after obtaining the continuous power spectrum;

S405. Perform noise reduction processing on the dynamic power spectrum, and use the noise-reduced dynamic power spectrum as a basis for quantitative ultrasound pulse Doppler blood flow.

The working principle of the above-mentioned technical solution is: the solution adopted in this embodiment is that in the spectrum analysis algorithm, since the Doppler echo signal is a non-stationary signal, the short-time Fourier transform is used to analyze the signal in the frequency domain, and the window function Select the effect that affects the processing, and choose the Hamming window as the window function in this paper. Because the existence of tissue clutter will drown the blood flow signal, the filter is used as the filter for pulse Doppler algorithm processing. After the actual signal is processed by the filter, the blood flow signal with low energy and high frequency is successfully extracted. The pulse Doppler algorithm is used to process the data, and the dynamic power spectrum of ultrasonic pulse Doppler is optimized.

In another embodiment, performing noise reduction processing on the dynamic power spectrum in said S405 includes:

S4051, extracting all characteristic components of the signal in the dynamic power spectrum;

S4052, analyzing the correlation relationship between two feature components; the correlation between different feature components is represented by an inner product;

The formula for calculating the correlation is as follows:

Among them, e _k represents the characteristic component of the slow echo signal, e _l represents the characteristic component of the correlation to be calculated, u _k represents the kth column of the matrix U, the U matrix is a left singular matrix, and v _k represents the kth column of the matrix V Column, V matrix is a right singular matrix; K represents the smallest integer greater than or equal to N/2, N represents the number of samples in the slow time set; Z _l represents the lth column of matrix Z. * Indicates the orthogonal relationship between e _k and e _l .

Therefore, the inner product between two feature components in the correlation relationship can be conveniently determined by the lower left element of the matrix.

S4053, if the main feature component is determined to be a clutter component according to the frequency threshold, calculate the correlation between the remaining feature components and the main feature component, and if the correlation is greater than a certain set correlation threshold, then judge that the feature component belongs to clutter Feature space, remove high feature components from the signal;

S4054. Form a set of clutter feature spaces according to step S4053, and reconstruct the filtered signal based on the set of clutter feature spaces.

Traditional filtering algorithms include projection-initialized IIR filter and polynomial regression filter. After the filter is designed, its cut-off frequency is fixed. When the tissue is moving rapidly, clutter with a large frequency shift will appear. In order to suppress the fast-moving clutter signal, the traditional filtering algorithm will set a larger cut-off frequency. At this time, it will inevitably filter out the clutter. At the same time, part of the blood flow signal is erroneously filtered out. It is precisely because the cutoff frequency of the traditional filtering algorithm cannot automatically adapt to the movement of the tissue, which ultimately leads to a decrease in the detection accuracy of the blood flow signal.

In order to suppress the clutter components in the slow time signal, it is necessary to determine whether each feature component belongs to the clutter feature space. Through the analysis of the feature components, it can be determined whether it belongs to the clutter feature space, and then filter processing. In terms of judging the dimensions of the clutter feature space, when the signal reconstruction method is changed, the correlation between the feature components can be easily obtained. The filtering algorithm of this embodiment adds a method for judging the correlation of the feature components, thereby It can more effectively filter out clutter components and improve the estimation accuracy of blood flow velocity.

In another embodiment, this embodiment provides an ultrasonic pulse Doppler blood flow measurement device, please refer to FIG. 4 , the device includes: an ultrasonic pulse Doppler probe, an interactive device, and a measurement control module;

The measurement control module is respectively connected to the ultrasonic pulse Doppler probe and the interactive device;

The ultrasonic pulsed Doppler probe includes several array elements arranged in an array, and the continuous several array elements are controlled by the measurement control module to transmit and receive ultrasonic waves to form sub-arrays;

The interaction device is used for the control operation interaction between the user and the measurement control module;

After the ultrasonic pulse Doppler blood flow measurement device is started, the interactive device displays whether the offset strategy condition is met, and if the offset strategy condition is met, after the ultrasonic pulse Doppler probe determines the physical position, based on the current physical position of the probe, determine The edge position of the array, and based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasound to offset the edge position, determine the position of the sub-array, and provide the user with sub-array position options, After the user selects the position of the corresponding sub-array through the interactive device, the ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the position of the sub-array; Quantitative measurement of Puller blood flow.

The working principle of the above-mentioned technical solution is: the solution adopted in this embodiment is that the device includes: an ultrasonic pulse Doppler probe, an interactive device, and a measurement control module;

The measurement control module is respectively connected to the ultrasonic pulse Doppler probe and the interactive device;

The ultrasonic pulse Doppler probe includes several array elements arranged in an array, and the measurement control module controls several array elements to transmit and receive ultrasonic waves to form a sub-array; the interactive device is used between the user and the measurement control module Interaction between control operations; after starting the ultrasonic pulse Doppler blood flow measurement device, the interactive device will display whether the offset strategy condition is satisfied, if the offset strategy condition is met, after the ultrasonic pulse Doppler probe determines the physical position, based on the current The physical position of the probe, determine the edge position of the array, and based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasound to the edge position, determine the position of the sub-array, and notify the user Subarray position options are provided. After the user selects the corresponding subarray position through the interactive device, ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the position of the subarray; Configure parameters for quantitative measurement of ultrasound pulsed Doppler blood flow.

The beneficial effect of the above technical solution is: the solution provided by this embodiment can automatically expand the steering angle by only modifying the physical position of the array elements participating in the current electronic beamforming, and even the limit that may have reached the user-configurable limit can be increased. The steering angle (plus or minus 20 degrees) is further expanded to automatically meet the Doppler measurement angle requirements to the greatest extent.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (10)

1. An ultrasonic pulsed Doppler blood flow measurement method, characterized in that, comprising: S100, determining the physical position of the pulse Doppler probe; S200, based on the current physical position of the probe, determine the array formed by the arrangement of several array elements in the probe, and determine the edge position of the array; S300. Based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasonic waves to shift to the edge position, and determine the position of the sub-array; S400, performing quantitative measurement of ultrasonic pulse Doppler blood flow based on the position of the subarray. 2. A method for measuring ultrasonic pulsed Doppler blood flow according to claim 1, wherein said S200 includes: when the array formed by several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array; Correspondingly, the S300 includes: connecting the first edge position and the position to be detected to form a first straight line; setting the first straight line and the direction of the blood vessel to form a first acute angle, and setting the second edge position to The positions are connected to form a second straight line; the second straight line and the direction of the blood vessel are set as a second acute angle, and it is judged whether the first acute angle is smaller than the second acute angle, and if so, adjust the sub-arrays for transmitting and receiving ultrasonic waves to the first of the array An edge position offset; if the first acute angle is greater than the second acute angle, adjust the sub-array for transmitting and receiving ultrasonic waves to the second edge position of the array; The direction of the blood vessel is a scalar quantity, and the relationship between the direction of the blood vessel and the direction of blood flow is as follows: when the direction of blood vessels is the same, the direction of blood flow includes: from left to right of the blood vessel, or from right to left of the blood vessel. 3. A method for measuring ultrasonic pulsed Doppler blood flow according to claim 1, characterized in that said S200 includes: when the array formed by several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array; Correspondingly, the S300 includes: S301, based on the current physical position of the probe, adjust the offset of the sub-array to the first edge position, and monitor whether the Doppler included angle is less than or equal to the standard Doppler included angle, if yes, execute step S302; if not, execute step S303; S302, adjusting the offset of the sub-array for transmitting and receiving ultrasonic waves to the first edge position of the array, and determining the first edge position as the position of the sub-array; S303, adjusting the offset of the sub-array for transmitting and receiving ultrasonic waves to the second edge position of the array, and determining the second edge position as the position of the sub-array. 4. A method for measuring ultrasonic pulsed Doppler blood flow according to claim 1, wherein said S200 includes: when the array formed by several array elements is a two-dimensional array, the edge position includes several edge positions; Correspondingly, the S300 includes: each edge position is connected with the position to be detected to form several straight lines, and each straight line forms an acute angle with the direction of the blood vessel, and the position of the array element corresponding to the straight line with the smallest acute angle is judged, and the array element is determined. The edge position corresponding to the element is set as the position of the sub-array. 5. A kind of ultrasonic pulse Doppler blood flow measurement method according to claim 1, is characterized in that, described S300 also comprises: S304, determining that the number of continuous sub-arrays transmitting and receiving ultrasonic waves in the probe is a selected number; S305, taking the outermost array element in the edge position of the array as a reference, continuously select array elements of the same number as the selected number inward as sub-arrays for transmitting and receiving ultrasonic waves, and determine the positions of the sub-arrays. 6. A kind of ultrasonic pulse Doppler blood flow measuring method according to claim 1, is characterized in that, before said S100 comprises: S500, start the ultrasonic pulse Doppler measurement mode; S600, judging whether the offset policy condition is met, if yes, execute step S100, if not, execute step S700; S700, using the current configuration parameters of ultrasonic pulse Doppler to perform quantitative measurement of ultrasonic pulse Doppler blood flow. 7. A kind of ultrasonic pulse Doppler blood flow measurement method according to claim 1, is characterized in that, described S300 also comprises: S306. When the position of the sub-array is shifted toward the edge position, a plurality of shift positions are formed, and according to the plurality of shift positions, the positions of the sub-array include multiple; S307, the positions of multiple sub-arrays are selected by the user through the interactive device, and the ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the current configuration parameters of the ultrasonic pulse Doppler according to the positions of the sub-arrays selected by the user. 8. A kind of ultrasonic pulse Doppler blood flow measurement method according to claim 1, is characterized in that, described S400 comprises: S401, based on the pulse Doppler spectrum received by the sub-array, use a spectrum analysis algorithm to input fixed-length data on the pulse Doppler spectrum, multiply the fixed-length data by the Hamming window each time, and use FFT processing to obtain Doppler power spectrum of Le data; S402, after the first spectrum analysis algorithm processing is completed, move the input Doppler data backward by the data of the step length, take the fixed-length Doppler data for the next spectrum analysis algorithm processing, and continuously sample The Doppler data cycle this operation to get the power spectrum changing with time; where the step length is determined by the current scanning speed; S403, after the spectrum analysis algorithm processes the current Doppler data, the power spectrum of the data will be obtained, the power spectrum corresponds to a spectral line in the dynamic power spectrum diagram, and the amplitude of the spectral line is mapped to an index table of gray values, It is coded and displayed according to the color indicated by the index table of the gray value; the larger the amplitude, the larger the gray value, indicating that the power at this frequency is high; S404, transfer to process the next set of data after processing the current data, and draw the dynamic power spectrum diagram of the Doppler signal after obtaining the continuous power spectrum; S405. Perform noise reduction processing on the dynamic power spectrum, and use the noise-reduced dynamic power spectrum as a basis for quantitative ultrasound pulse Doppler blood flow. 9. A kind of ultrasonic pulse Doppler blood flow measurement method according to claim 8, is characterized in that, in described S405, carries out denoising processing to dynamic power spectrogram, comprises: S4051, extracting all characteristic components of the signal in the dynamic power spectrum; S4052, analyzing the correlation relationship between two feature components; the correlation between different feature components is represented by an inner product; S4053, if the main feature component is determined to be a clutter component according to the frequency threshold, calculate the correlation between the remaining feature components and the main feature component, and if the correlation is greater than a certain set correlation threshold, then judge that the feature component belongs to clutter Feature space, remove high feature components from the signal; S4054. Form a set of clutter feature spaces according to step S4053, and reconstruct the filtered signal based on the set of clutter feature spaces. 10. An ultrasonic pulsed Doppler blood flow measurement device, characterized in that it comprises: an ultrasonic pulsed Doppler probe, an interactive device, and a measurement control module; The measurement control module is respectively connected to the ultrasonic pulse Doppler probe and the interactive device; The ultrasonic pulsed Doppler probe includes several array elements arranged in an array, and the continuous several array elements are controlled by the measurement control module to transmit and receive ultrasonic waves to form sub-arrays; The interaction device is used for the control operation interaction between the user and the measurement control module; After the ultrasonic pulse Doppler blood flow measurement device is started, the interactive device displays whether the offset strategy condition is met, and if the offset strategy condition is met, after the ultrasonic pulse Doppler probe determines the physical position, based on the current physical position of the probe, determine The edge position of the array, and based on the blood flow direction of the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasound to offset the edge position, determine the position of the sub-array, and provide the user with sub-array position options, After the user selects the position of the corresponding sub-array through the interactive device, the ultrasonic pulse Doppler blood flow quantitative measurement is performed based on the position of the sub-array; Quantitative measurement of Puller blood flow.